Worm-drive and compensating gearing.



D. B. ROSS. WORM DRIVE AND GOMPBNSATING GBARING.

APPLICATION FILED IDEO. 16, 190B.

'Patented A 8,1911.

COLUMBIA Mmm C0. WAXHINL'I'IUN- D- C.

run STATES PATENT onrrcn.

DAVID E. ROSS, OF BROOKSTON, INDIANA, ASSIGNOR TO THE ROSS GEAR @t TOOLCOMPANY, OF LA FAYETTE, INDIANA, A CORPORATION OFINDIANA.

WORM-DRIVE AND COMPENSATING- GEARING.

To all whom 'it may concern:

Be it known that I, DAVID E. Ross, a citizen of the United States,residing at Brookston, in the county of White and State of Indiana, haveinvented a certain new and useful Improvement in Worm-Drives andCompensating Gearing, of which the following is a full, clear, and exactdescription, reference being had to the accompanying drawino's.

tThis invention relates generally to devices for driving shaft o-r axlesections, and it has particular reference to a worm-gear for drivingsaid sections and to the compensating gearing through which saidsections may be driven at different rates of speed.

The obj ect of the invention is to provide a device of the characterstated which shall be simple and economical in construction andefficient in operation.

|Ihe more specilic features of my invention will appear from thefollowing specilication taken in connection' with the accompanyingdrawings, in which- Figure 1 is a sectional view taken in the plane ofthe axle sections; and Fig. 2 is a sectional view Vtaken centrallythrough Fig. 1 at right angles to the axle sections.

Taking up a detailed description of my invention by the use of referencecharacters, 1 and 2 represent the adjacent ends of the axle or shaftsections, the construction illustrated being specially adapted for usein automobiles in which case the said sections would represent the innerportions of the rear axle sections of the automobile. The inner ends ofthe axle sections are made irregular or non-cylindrical in cross sectionso as to provide a driving engagement with the bevel gears 3 and 4 whichare mounted upon the ends of the axle sections 1 and 2 respectively.These irregular portions of the axles may be formed in any practicalway, or the gears may be keyed to the sections, as is common in suchconstructions, the gears being held in place by nuts 3 and 4 which screwon their respective axle sections. Surrounding the axle sections 1 and 2are the tubular housings 5 and 6, which extend outwardly from the maingear casing toward the ground wheels for the rear axle sections.Surrounding the inner ends of the said tubular housings are the sections7 and 8 of the main gear casing, the said casing being divided on avertical plane through the center',

Specification of Letters Patent.

Application led December 16, 1908.

Patented Aug. 8, 1911.

serial No. 467,776.

the driving gears and their various bearings, hereinafter described,being contained within said casing. The sections of the casing aresecured together in any suitable manner, as by bolts passing throughopenings 9 in the outer adjacent edges of said sections.

Within the casing sections adjacent the respective ends of the tubularhousings 5 and 6 are roller-bearing rings 10 and 11, lin raceways inwhich rotate the balls 12 of said bearing. Within the rings 10 and 11,and having the coperating race-ways for the balls, are rings 13 and 14,the same being mounted upon the outer tubular ends 15 and 16respectively of gear housings 17 and 18, the extensions 15 and 16 beingin axial alinement with the tubular housings 5 and 6 and being boredwith an internal diameter substantially the same as that of said tubularhousings. At the inner ends of said extensions 15 and 16, the housings17 and 18 flare outwardly so as to form, when assembled, anapproximately spherical shell, each of said housing sections beingprovided with an annular flange at 19 and 20 respectively, by

means of which the said sections may be secured to a worm-wheel 21, thehousing sections being secured to said wheel in any suitable manner, asby screws or bolts passing through the anges and through openings 22 inthe said wheel. IVithin the flared portions of the respective housingsections, I provide annular shoulders 23 which are adapted to projectover the hubs of the respective gears 3 and 4, the housing sections thusbeing journaled upon the hubs of said gears and being separatedtherefrom by bushings 24 so as to prevent excessive wear. These housingsections are therefore journaled within the casing sections 7 and 8 andupon the hubs of the said gears.

Secured to the worm gear 21 by means of keys 25, is a spider 26, saidspider carrying a series of ournal-pins 27 for planetary pinions 28,there being one of these pinions journaled upon each of said pins, saidpinions meshing with each of the gears 3 and 4. The spider 26 iscircular on its outer periphery to conform to the circumference of theworm gear, and its inner portion is also substantially circular to fitabout inwardly extending flanges on the gears 3 and 4. Between theplanetary pinions, the spider is provided with inwardly extending armsor spokes which materially strengthen the conllil struction of thespider. In order to prevent the journal pins 27 from rotation, and toapply the driving power directly to the pins, the heads of the pins areslotted so as to form a Way for the keys 25, the spider frame being thussecured to the Worm gear by the keys which extend through the hea-ds ofthe journal pins.

To take up the end thrust of the housing sections, ball bearings areemployed at each end of the housing, t-he same being shown at 29 and 30.

In its upper part, the main casino' sections T and 8 are so constructedas to form a tubular housing .for the drive shaft 3l, said shaft beingpreferably squared at its end 32 for convenient attachment to the maindriving mechanism of the device. Near its center, the shaft section isprovided with a driving Worm 32 which meshes With teeth on the Worm gear2l, whereby the latter is driven and, through the connectionshereinbefore described, motion is imparted to the axle sections. As Willbe understood, the pitch of the threads on the Worm should be such as torotate the worm Wheel at the desired speed with the leastamount offriction possible When the Worm is driven, and yet the pitch should alsobe such as to make it possible to push the automobile about When desiredWithout running the engine or for permitting the same to coast when.going down an incline. In the construction of the Worm, I have foundthat an angle of 25 degrees of the helix formed by the threads on theworm is practical, and at present I prefer to use substantially thisangle. The shaft seetion 3l and the Worm 32 thereon are preferablyintegral in construction, and at the end of the Worm the said section ispreferably provided with annular extensions or flanges against whichthrust bearings 3a may operate. The journal bearings for the shaftsections are shown at 85 and 36.

The sections of the casing 7 and 8 may be supported Within the machinein any desired manner, and, for strengthening the construction, a trussrod 37 may be employed, the same preferably passing through one of theperforations 9 in the lower part of the casing sections.

I-Iaving thus described my invention, what I claim is:

l. In gearing, the combination With a pair of alined shaft or axlesections, of bevel gears secured to the adjacent ends of said sections,a Worm gear mounted co-axially with respect-to the said sections, aspider Within the said Worm gear, one or more journal pins mountedradially in said spider, said pins being provided with slots in theirouter ends, keys connecting the spider and the Worm gear and passingthrough the slots in the ends of said journal pins, a planetary pinionmounted on each of said pins and 99eme meshing with each of the saidgears, and a worm meshing With and driving the Worm gear.

2. In gearing, the combination with a pair of axle or shaft sections, ofbevel pinions secured to the adjacent ends of the respective sections, adriving member mounted co-axially With respect to the said sections,means for driving said member, a spider Within the said member, one ormore journal pins mounted radially in the said spider, each of said pinsbeing provided with key slot in its outer end, keys passingthrough saidslots and through corresponding slots in the said member whereby thespider, the pins and the member are secured together, and a planetarygear journaled on each of said pins and meshing with the gear on each ofthe said sections.

3. In gearing, the combination With a pair of alined shaft or axlesections, of a gear for and secured to the inner end of each of saidsections, a Worm Wheel mounted coaxially with respect to the saidsections, a spider frame Within the said Worm Wheel, one or more journalpins extending radially in the said spider frame, each of said pinsbeing provided With a key slot in its outer end, a key for each of saidpins, said keys lying in the slots in the pins and extending intocorresponding slots in the Worm Wheel, a

planetary pinion journaled on each of said pins and meshing With thegears on the said sections, a pair of housing sections inclosing thesaid gears and pinions and turning with the spider, said housinOsections each being journaled on the hubs of the said gea-rs, a gearcasing surrounding the said shaft or axle sections and inclosing theWorm Wheel and the housing sections, a Worm journaled in the said. gearcasing and meshing with the Worm Wheel for driving the latter, androller bearings between the gear casing and the housing sections forholding the latter in position.

4. In gearing, the combination With a pair of alined shaft or axlesections, of a bevel gear for and secured to the inner end of each ofsaid sections, a Worm Wheel mounted co-axially with respect to the saidsections, a spider frame Within the said Worm wheel, one or more journalpins extending radially in the said spider frame, each of said pins beinprovided with a key slot in its outer end, a key for each of said pins,said keys lying in the slots in the pins and extending intocorresponding slots in the vrorm Wheel, a planetary pinion journaled oneach of said pins and meshing with the gears on the said sections, apair of housing sections secured to the Worm wheel and inclosing thesaid gears and pinions, said housing sections each being journaled onthe hubs of the said bevel gears, a gear casing surrounding the saidshaft or axle sections and inclosing the worm wheel and the housingsections, a worm journaled in the said gear casing and meshing with theworm wheel for driving the latter, and roller bearings between the gearcasing and the housing sections for holding the latter in position.

5. In gearing, the combination with a pair ot' alined shaft or axlesections, of a bevel gear for and secured to each of the said sections,a worm wheel mounted co-aXially with respect to the said sections, aspider frame within the said worm Wheel, a plurality of ournal pinsmounted radially in the said spider frame, the outer ends of said pinsterminating adjacent the worm wheel and being provided with transverselrey slots at their ends, a key for each of said journal pins extendingthrough the slot in the end of the latter and into the said Worm Wheelwhereby the spider frame, the pins and the worm wheel are securedtogether', a

planetary pinion journaled on each of said pins and meshing with thesaid gears on the shaft or axle sections, a pair of housing sectionssecured to the worm wheel and sur-` rounding the said gears, eachsection of the housing being journaled upon the hub of its respectivegear, a pair of gear case sections surrounding the aXle sections and thesaid housing sections, said casing sections being adapted to be securedtogether, a driving worm journaled in the said casing sections andmeshing with tlie worm wheel, and roller bearings between the casingsections and the housing sections Jfor holding the latter in positionwithin the casing sections.

1n testimony whereof, I hereunto aiiix my signature in the presence ottwo witnesses.

DAVID E. ROSS.

Witnesses:

WILLIAM Ross, EDWARD A. Ross.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents.

Washington, D. C.

